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ORPHA:574

21q deletion syndrome

high confidenceDisorder

Also known as: 21q- syndrome · Partial 21q monosomy

Publications

36

30.1th percentile

Trials

0

Interventional, condition-specific

Researchers

254

Distinct authors in sample

Gene link

—

Readiness

2/6

Stages with a signal

Clinical definition (Orphanet)

Monosomy 21 is a chromosomal anomaly characterized by the loss of variable portions of a segment of the long arm of chromosome 21 that leads to an increased risk of birth defects, and intellectual deficit.

How rare: <1 / 1 000 000 — fewer than one in a million. In a city the size of Kolkata, that might mean on the order of fifteen people.

Orphanet entry

Cross-references

Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.

Additional Mondo synonyms (2)

monosomy type 21 · partial 21q monosomy

Research stages

Trial readiness signals

Where this condition sits on an open-data research pipeline — not how close a treatment is, and not medical advice. Empty stages often mean “not in these databases under this Mondo ID,” not “impossible.”

2/6 stages with a signal

Research-stage checklist from open sources (GenCC, literature, Monarch when enriched, ClinicalTrials.gov). Not a prognosis or care recommendation.

  1. Gene identifiedNot found

    No GenCC disease–gene assertion in this build

  2. LiteraturePresent

    36 matched papers (12 in last 10 years) Source

  3. Phenotype characterisedPresent

    26 HPO annotations (e.g. Failure to thrive in infancy; High palate; Epicanthus) Source

  4. Animal modelNot found

    No Alliance genotype “model of” associations via Monarch for these Mondo IDs

  5. Orphan designationNot found

    No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source

  6. Interventional trialNot found

    No matched interventional trial under our ClinicalTrials.gov rules

Biology

Genes and phenotypes

Gene–disease validity from GenCC, plus phenotypes and animal models joined from Monarch Initiative via Mondo ID — not a clinical diagnosis aid.

Do we know what causes it?

Not yet — the cause hasn't been pinned down in GenCC.

No strong gene–disease assertion joined for this Orphanet entity.

Phenotypes (Monarch / HPO)

26

Associated phenotypes · MONDO:0018930

  • Failure to thrive in infancy
  • High palate
  • Epicanthus
  • Low anterior hairline
  • Microretrognathia

Showing 5 of 26 — open Monarch for the full list.

Animal models (Monarch / Alliance)

None returned for this Mondo ID. Empty here is not proof that no model organism work exists under another name or gene.

Monarch fetch 2026-07-29

Therapies

Designations, candidates, and chemicals

FDA OOPD and EMA orphan designations, Open Targets clinical candidates, and CTD chemical associations via MyDisease.info. These never change the interventional-trial headline.

Orphan designation (FDA · EMA)

No designation matched this disease via UMLS or preferred name on the FDA OOPD mirror or EMA orphan register. Absence here is not proof that none exists under another wording.

Open Targets candidates

No drugs or clinical candidates returned for this Mondo ID on Open Targets.

CTD chemicals (MyDisease.info)

No CTD chemical associations returned for this Mondo ID.

Literature

Is anyone studying this?

36

36 papers have ever been published on this condition (under this name). For scale, breast cancer has over 700,000. Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.

36 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 59 (publications denominator n=3967).

12 in the last 10 years · high confidence · 30.1th percentile (publications denominator)

Phrase hits: 36 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

254

Distinct author names in 36 sampled papers — named people below.

Who's working on it?

No interventional trial matched this name; these authors publish on it in the sampled literature — a practical starting point for contact.

  1. 01
    Bartsch O2 papers · 2004

    Institut für Klinische Genetik, Universitäts Klinikum der Technischen Universität, Dresden, Germany.

    Papers in Europe PMC
  2. 02
    Ahmed MZ1 paper · 1997
    Papers in Europe PMC
  3. 03
    Aizawa Y1 paper · 2025

    School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan.

    Papers in Europe PMC
  4. 04
    Allahyari M1 paper · 2019

    Department of Pediatrics, UCSD School of Medicine, La Jolla, CA, USA.

    Papers in Europe PMC
  5. 05
    Andria G1 paper · 2011
    Papers in Europe PMC
  6. 06
    Antonarakis SE1 paper · 1994
    Papers in Europe PMC
  7. 07
    Ashaat EA1 paper · 2020

    Clinical Genetics Department, National Research Centre, Cairo, Egypt.

    Papers in Europe PMC
  8. 08
    Ayyanar P1 paper · 2025

    Department of Pathology and Laboratory Medicine, All India Institute of Medical Sciences, Bhubaneswar, Bhubaneswar, IND.

    Papers in Europe PMC
  9. 09
    Azad AK1 paper · 2020

    Department of Pathology/Molecular Pathology, Montefiore Medical Center, Albert Einstein College of Medicine, 1635 Poplar St., Bronx, NY 10461 USA.

    Papers in Europe PMC
  10. 10
    Bacino CA1 paper · 2016

    Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Texas Children's Hospital, Houston, TX 77030, USA.

    Papers in Europe PMC

Clinical research

Is a treatment being tested?

0

interventional trials for this specific condition

No interventional trial testing a treatment matched this specific condition name on ClinicalTrials.gov (observational studies and pan-disease registries are listed separately when present).

Data as of 11 September 2026 · last trial check 11 September 2026

No matched interventional trials. This is true for 77.2% of diseases in the trials denominator (5501 of 7126). Here are the researchers publishing on it.

high confidence · 38.6th percentile (trials denominator)

Recruiting interventional trials

From the matched ClinicalTrials.gov set

No interventional trial testing a treatment was found for this specific condition name on ClinicalTrials.gov.

See who's working on it — people publishing on this disease are often the practical next contact when no trial is listed.

Other registries (secondary)

Broader net from EU CTIS, ISRCTN, and ICTRP when available — deduped against ClinicalTrials.gov IDs already counted above. Dual-model LLM relevance gates what we keep. These rows are not added to the interventional headline.

raw 0 · after dedupe 0 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 0 · dropped 0 · fetched 2026-07-29

Source notes: ictrp: Error: ICTRP public search unavailable (WHO portal is SPA-only; SOAP needs partnership). Tried: https://apps.who.int/tri

No secondary-registry studies passed dual-model relevance for this condition name (after dedupe).

Where to find support

Condition-specific patient organisations, when Orphanet lists them, are on the disease’s Orphanet page. We also link umbrella groups that support undiagnosed and ultra-rare families.

Orphanet entry for 21q deletion syndrome — check Associations / patient organisations on that page.

India — NPRD

Last verified 2026-07-26

This ORPHAcode is not on our curated NPRD list (direct or Mondo-parent match). That does not decide clinical eligibility; families in India should ask a notified Centre of Excellence about current coverage.

Hand-curated for this project. ORPHAcode mappings are best-effort and may be incomplete or imprecise for umbrella categories. Parent (Mondo) matches mean the policy lists a broader category — confirm eligibility with a Centre of Excellence. Financial entitlements summarised from public policy statements and may change. This is not official government guidance.

How we counted this

Europe PMC query (preferred label + any corrected label + Orphanet and Mondo exact synonyms, stoplisted; unioned with resolved MeSH labels when available). UMLS / OMIM / NCIT cross-references are stored on the overview but are not added to the query string.

"21q deletion syndrome" OR "21q- syndrome" OR "Partial 21q monosomy" OR "monosomy type 21"

Run this search on Europe PMC

ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):

"21q deletion syndrome" OR "21q- syndrome" OR "Partial 21q monosomy" OR "monosomy type 21"

Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.

Query health: ok — strategies attempted: phrase; with hits: phrase

Run this search on ClinicalTrials.gov

Confidence reasoning

  • Preferred label is multi-word and distinctive
  • No synonyms dropped by stoplist
  • No label/synonym collisions with other diseases in this corpus

Ingested 2026-07-26T14:24:32.249Z